Miwa C, Sugiyama Y, Iwase S, Mano T, Ohira Y, Grigoriev A, Kozlovskaya I, Egorov A, Shenkman B
Department of Autonomic Neuroscience, Nagoya University, Japan.
Environ Med. 1997 Dec;41(2):135-7.
In this study we examined the effects of 3 days of dry immersion on heart rate variability (HRV) and blood pressure variability (BPV) in response to head-up tilting in 4 healthy young subjects aged 21 to 36 years. Resting value of the high-frequency (HF) power of BPV and HRV decreased, while the low-frequency (LF)/HF ratio of HRV and blood pressure increased after the dry immersion. The HF power of HRV decreased, while the LF/HF ratio of HRV and heart rate increased during head-up tilting before and after dry immersion. All powers of BPV and BP were unchanged during head-up tilting. The values of the decrease in the HF power of HRV and the increase in the LF/HF ratio during head-up tilting after dry immersion were larger than those before. These results suggest that 3 days of dry immersion altered the autonomic balance toward the sympathetic dominant at rest, and that cardiac function may play a crucial role in BP maintenance during head-up tilting compared with vasoconstrictor function.
在本研究中，我们检测了4名年龄在21至36岁的健康年轻受试者在经历3天的干浸后，其心率变异性（HRV）和血压变异性（BPV）对头部直立倾斜的反应。干浸后，BPV和HRV的高频（HF）功率静息值降低，而HRV和血压的低频（LF）/HF比值升高。在干浸前后的头部直立倾斜过程中，HRV的HF功率降低，而HRV和心率的LF/HF比值升高。在头部直立倾斜过程中，BPV和血压的所有功率均未改变。干浸后头部直立倾斜过程中HRV的HF功率降低值和LF/HF比值升高值均大于干浸前。这些结果表明，3天的干浸使静息时自主神经平衡向交感神经占主导方向改变，并且与血管收缩功能相比，心脏功能在头部直立倾斜过程中血压维持方面可能起关键作用。
